60 Amp Alternator wiring question

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vms1942
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60 Amp Alternator wiring question

Unread post by vms1942 » August 31st, 2014, 10:18 pm

I need help with wiring a NOS 60 amp alternator.

Bare with me guys, this is the first M151 I have restored, but I need your help on this.

I bought a NOS 60 amp Alternator to install on an M151a1. The vehicle came with an aftermarket 60 amp alternator and the leads are cut, and I have replaced the wiring harness with a new one from Vintage Wiring of Maine.

The schematics that came with the harness show three wires going to the alternator, #5, #3, # 568, The new alternator has one wire coming from it which I assume plugs into the #5 by separating the metal connector (I don’t know why this connector came with a 60 amp harness, but it is tagged #5 and has a rubber connector to remove the metal connector.

My pictures can better describe my situation. I had a friend send me a photo of his 60amp alternator wiring and I placed my questions etc. on that photo which is included below.

Hopefully one of you M151 Guru's can tell me how to wire this?

Image
Photo #1 : Wiring for alternator from Vintage Wiring of Maine

Image
Photo #2: Inside Connector

Image
Photo #3: Wiring connector on my NOS 60 amp alternator

Image
Photo #4: Photo of my friends M151 (A2 engine?) 60 amp alternator / I have written questions, etc on the photo.
1942 WC-54, Restored and now in Fagen Memorial Museum, Granite Falls, MN
1942 Ben Hur Trailer Completed
1942 M3 Anti Tank Gun (Missouri Military Academy)
1944 MB tub (made one from two bad ones. one wrecked back and one wrecked front) Completed
1942 GPW, Matching serial numbers (Restoration pending)
1945 WC-51 Completed
1966 M151a1, Completed

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svramselaar
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Re: 60 Amp Alternator wiring question

Unread post by svramselaar » September 1st, 2014, 4:11 am

hi

you do not need the steel plug only the rubber one
the 568 wire is the thin one with the rubber connector (it must get hot as the contact is on )
wire 3 is the ground it go at the bolt next to the cover with warning on it
wire 5 is the wire to the batts (constant hot ) get the cover with warning of ( two screws )
untherneeth is a bolt for the wire

the wire`s 3 and 5 have different size eye on it so you can not do it wrong

george

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Re: 60 Amp Alternator wiring question

Unread post by Fil Bonica » September 1st, 2014, 10:15 am

George's instructions are good.
Just make sure you Don't reverse the two big wires.
Sparks could fly when you connect the batteries.
Ask me why!!!

Fil Bonica
K1ABW

vms1942
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Re: 60 Amp Alternator wiring question

Unread post by vms1942 » September 1st, 2014, 10:38 am

Thanks for the help guys.

The #5 is connected to the hot side of the foot starter switch terminal, but is about a 10 gauge wire, maybe an 8. Is this large enough to carry the load?

Greg
1942 WC-54, Restored and now in Fagen Memorial Museum, Granite Falls, MN
1942 Ben Hur Trailer Completed
1942 M3 Anti Tank Gun (Missouri Military Academy)
1944 MB tub (made one from two bad ones. one wrecked back and one wrecked front) Completed
1942 GPW, Matching serial numbers (Restoration pending)
1945 WC-51 Completed
1966 M151a1, Completed

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whiterabbit
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Re: 60 Amp Alternator wiring question

Unread post by whiterabbit » September 1st, 2014, 11:13 am

Looks like 2 maybe 4 gauge running to the terminal on the starter switch.
"It’s the unconquerable soul of man, not the nature of the weapon he uses, that insures victory." Gen. George Patton

1986-2014 Ordnance Corps RETIRED!
XVIII Airborne Corps Combat Affiliation
Go Ordnance!
1972 M151A2
1978 exMOD 109 Land Rover S3 (sold)
1942 WLA
M274 (sold) Big mistake. Sigh....

vms1942
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Re: 60 Amp Alternator wiring question

Unread post by vms1942 » September 1st, 2014, 12:16 pm

whiterabbit wrote:Looks like 2 maybe 4 gauge running to the terminal on the starter switch.
That's what I was thinking also. The picture of my friends alternator definitely has a much larger wire.
The schematics I received with the harness are confusing at best. They basically sent me poor copies of what are in the manuals with numbers that are very small and blurred. The best copy was for an A2 which doesn't exactly match up to the A1 harness.
1942 WC-54, Restored and now in Fagen Memorial Museum, Granite Falls, MN
1942 Ben Hur Trailer Completed
1942 M3 Anti Tank Gun (Missouri Military Academy)
1944 MB tub (made one from two bad ones. one wrecked back and one wrecked front) Completed
1942 GPW, Matching serial numbers (Restoration pending)
1945 WC-51 Completed
1966 M151a1, Completed

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Re: 60 Amp Alternator wiring question

Unread post by halftracknut » September 1st, 2014, 12:30 pm

before you put power on that...I think you need a 30 amp generator and separate voltage regulator set up....If you change to an alternator I do believe there is a kit to do that I have seen them sold on e-bay...however I have never made this modification...only what seen posted ....I would hate to see you burn that nice alt. up....try to ask rick he may remember more about this and hid jeep is an A-1....
slowest mutt east of the missippi..

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whiterabbit
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Re: 60 Amp Alternator wiring question

Unread post by whiterabbit » September 1st, 2014, 3:03 pm

You have a 1966? Did you order a early 30amp generator harness or is the new harness for a jeep with a 60 amp alternator? I have seen the kits on fleabay to use a 60amp alt in a 30amp gen truck. Pretty cheap.
Top of the forum pages has a link to all the manuals, "G838 manuals", nice crisp clear manuals. :D You need the -20 ones. They're for the units mechanics.
Number code for the wiring harness's tags. :D
http://olive-drab.com/od_mseries_circuits.php
"It’s the unconquerable soul of man, not the nature of the weapon he uses, that insures victory." Gen. George Patton

1986-2014 Ordnance Corps RETIRED!
XVIII Airborne Corps Combat Affiliation
Go Ordnance!
1972 M151A2
1978 exMOD 109 Land Rover S3 (sold)
1942 WLA
M274 (sold) Big mistake. Sigh....

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muttguru
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Re: 60 Amp Alternator wiring question

Unread post by muttguru » September 1st, 2014, 5:13 pm

Whiterabbit has asked the most important question. What front harness is fitted to your M151A1?
There was a special front harness issued especially designed for conversion of the M151 and M151A1 vehicles, converting them from a 28v generator w/regulator to a 28v 60-amp alternator. This harness had the connectors to power the fuel pump safety switch but included the terminals which connected to the alternator. It was similar to, but not the same as, the standard M151A2 front harness. You can see what it looks like in TM9-2320-218-34P on pages 62-0 through to 62-2. You can see the connections for the alternator in the drawing. Study the drawing closely and compare it to what you have.
NOTE: the Military called the alternator a "generator-internally rectified" which is factually correct but a bit misleading....it's NOT the same as the standard 28v generator usually found on pre-A2 models.

In addition to this special harness, there was a "cheap and cheerful" conversion used on pre-A2 models which consisted of a wiring kit which could be used on any M-series vehicle, including big trucks like the 2.5 tonners, to install an alternator in place of a generator. If this kit was used on an M151 or A1, the wiring had to be shortened as appropriate. Jeff at Frontline has this kit and IIRC, the kit includes instructions too.

I think you should first determine whether the front harness on your vehicle is in fact the same as the one shown in the 34P, or whether the harness is an original M151A1 harness which has used the conversion kit.
Whatever you have, it should be able to connect to the alternator you have purchased.

Ken

ADDITION.
I looked at the picture you posted showing the metal connector. I think the harness provided by VWoM is a harness for an M151A1 that can be used in comjunction with the old 28v generator (the metal connector goes to the regulator box outlet) and it can also be used in conjunction with the 60-amp alternator, in which case the metal connector is disconnected at the rubber plug and the rubber plug connects directly to the alternator... BUT the other wires should still be there...not cut off from the harness.
K
Kind regards....
Ken

Always wanted - Details and pictures of M416 Trailer data plates & M151 data plates & body-tags for my research. Thanks!

Contact address - - muttguru@aol.com

Note for 2023..... Ken..."Less Stress - More Exercise!"

vms1942
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Re: 60 Amp Alternator wiring question

Unread post by vms1942 » September 1st, 2014, 10:04 pm

muttguru wrote:Whiterabbit has asked the most important question. What front harness is fitted to your M151A1?
There was a special front harness issued especially designed for conversion of the M151 and M151A1 vehicles, converting them from a 28v generator w/regulator to a 28v 60-amp alternator. This harness had the connectors to power the fuel pump safety switch but included the terminals which connected to the alternator. It was similar to, but not the same as, the standard M151A2 front harness. You can see what it looks like in TM9-2320-218-34P on pages 62-0 through to 62-2. You can see the connections for the alternator in the drawing. Study the drawing closely and compare it to what you have.
NOTE: the Military called the alternator a "generator-internally rectified" which is factually correct but a bit misleading....it's NOT the same as the standard 28v generator usually found on pre-A2 models.

In addition to this special harness, there was a "cheap and cheerful" conversion used on pre-A2 models which consisted of a wiring kit which could be used on any M-series vehicle, including big trucks like the 2.5 tonners, to install an alternator in place of a generator. If this kit was used on an M151 or A1, the wiring had to be shortened as appropriate. Jeff at Frontline has this kit and IIRC, the kit includes instructions too.

I think you should first determine whether the front harness on your vehicle is in fact the same as the one shown in the 34P, or whether the harness is an original M151A1 harness which has used the conversion kit.
Whatever you have, it should be able to connect to the alternator you have purchased.

Ken

ADDITION.
I looked at the picture you posted showing the metal connector. I think the harness provided by VWoM is a harness for an M151A1 that can be used in comjunction with the old 28v generator (the metal connector goes to the regulator box outlet) and it can also be used in conjunction with the 60-amp alternator, in which case the metal connector is disconnected at the rubber plug and the rubber plug connects directly to the alternator... BUT the other wires should still be there...not cut off from the harness.
K
Whiterabbit & Muttguru,

NO my harness from VWoM is not like the one illustrated in TM9-2320-218-34P. I only have one wire going from the harness to the alternator which is the one that I can separate from the metal connector. Based on what I see now I assume it means I need to get the 60 amp adapter kit.

I sure appreciate everyone's help on this.
1942 WC-54, Restored and now in Fagen Memorial Museum, Granite Falls, MN
1942 Ben Hur Trailer Completed
1942 M3 Anti Tank Gun (Missouri Military Academy)
1944 MB tub (made one from two bad ones. one wrecked back and one wrecked front) Completed
1942 GPW, Matching serial numbers (Restoration pending)
1945 WC-51 Completed
1966 M151a1, Completed

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Re: 60 Amp Alternator wiring question

Unread post by Fil Bonica » September 1st, 2014, 10:16 pm

Pm me if you need the conversion harness.

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svramselaar
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Re: 60 Amp Alternator wiring question

Unread post by svramselaar » September 2nd, 2014, 5:00 am

hi

witch wire`s come out your harnass for the alternator :?: :?:
how thick are they :?: :?:
568 at the picture is ok
wire`s 3 and 5 must be i think aboud gage 6
http://www.nachi.org/forum/attachments/ ... arison.jpg

if you have a thick wire 3 and it go to ground (the other side go at a bolt left fender )
also for wire 5 wen it is thick and go to the starter switch ( positive side )
it must work

george

vms1942
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Re: 60 Amp Alternator wiring question

Unread post by vms1942 » September 2nd, 2014, 9:44 am

The only wire coming from my harness is the #5 with a rubber connector that allows me to remove the metal connector which is tagged 568. No other wires at all for the alternator. According to your photo link, The #5 is a 10 gauge and so is the 568. I'm ordering a 60 amp conversion kit today.
1942 WC-54, Restored and now in Fagen Memorial Museum, Granite Falls, MN
1942 Ben Hur Trailer Completed
1942 M3 Anti Tank Gun (Missouri Military Academy)
1944 MB tub (made one from two bad ones. one wrecked back and one wrecked front) Completed
1942 GPW, Matching serial numbers (Restoration pending)
1945 WC-51 Completed
1966 M151a1, Completed

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Re: 60 Amp Alternator wiring question

Unread post by muttguru » September 2nd, 2014, 3:09 pm

vms1942 wrote:The only wire coming from my harness is the #5 with a rubber connector that allows me to remove the metal connector which is tagged 568. No other wires at all for the alternator. According to your photo link, The #5 is a 10 gauge and so is the 568. I'm ordering a 60 amp conversion kit today.
Here's what it should look like. When you get it, I'd really appreciate a copy of the installation instructions for my file :)

Image

ken
Kind regards....
Ken

Always wanted - Details and pictures of M416 Trailer data plates & M151 data plates & body-tags for my research. Thanks!

Contact address - - muttguru@aol.com

Note for 2023..... Ken..."Less Stress - More Exercise!"

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whiterabbit
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Re: 60 Amp Alternator wiring question

Unread post by whiterabbit » September 2nd, 2014, 5:47 pm

This is on my 1972 A2 for the 60amp
Image
This is the Alt. ground on the body. This goes to the ground bolt outside next to the alt's terminal cover.
Image
And the soldered on wire coming off the alt.
Image
"It’s the unconquerable soul of man, not the nature of the weapon he uses, that insures victory." Gen. George Patton

1986-2014 Ordnance Corps RETIRED!
XVIII Airborne Corps Combat Affiliation
Go Ordnance!
1972 M151A2
1978 exMOD 109 Land Rover S3 (sold)
1942 WLA
M274 (sold) Big mistake. Sigh....

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